Perovskite Nanocrystals In Situ Encapsulated in TiO₂ Microspheres for Stable CO₂ Photoreduction in Water

Abstract

Photoreduction of carbon dioxide (CO2) into fuels presents a promising approach to mitigate global warming and energy crises. Halide perovskite nanocrystals (NCs) with prominent optoelectronic properties have triggered substantial attention as photocatalysts but are limited by the charge recombination and instability. Here, we develop stable CsPbBr3/titania microspheres (TMs) by in situ growth of CsPbBr3 NCs inside mesoporous TMs through solid-state sintering, which significantly improves the stability of perovskite NCs, making them applicable in water with efficient CO2 photoreduction performance. Notably, the CsPbBr3/TMs demonstrates a 6.73- and 9.23-fold increase in the rate of CH4 production compared to TMs and CsPbBr3, respectively. The internal electric field facilitates S-scheme charge transfer, enhancing the separation of electron–hole pairs, as evidenced by X-ray photoelectron spectroscopy and electron paramagnetic resonance analysis, which is pivotal for the selective photoreduction of CO2. These insights pave the way for the design of CsPbBr3-based photocatalysts with superior efficiency and stability.

Exploring the Effects of Structural and Surface Modifications of Lead Halide Perovskite Nanocrystals on Photocatalytic CO2 Reduction: A Holistic Perspective

“…A few other stabilization strategies are further highlighted below, wherein the stability of the perovskite catalyst is ensured even without compromising performance. A recent work by Zou et al reported the in situ growth of CsPbBr 3 nanocrystals inside as synthesized microspheres of TiO 2 by employing the solid-state sintering method . This improves the stability of PNCs, making them suitable for photoreduction in water.…”

Halide perovskite for enhancing photocatalytic efficiency: basic characteristics, nanostructure engineering and applications

“…CsPbBr 3 QDs and Ag nanoparticles were anchored on the surface of g-C 3 N 4 sheets, which not only accept photo-induced electrons from the CsPbBr 3 QDs, but also act as an electron-transport tunneling to transfer photo-induced electrons to the Ag nanoparticles for the reduction of CO 2 . The catalytic system developed by Zou et al 146 for the in situ growth of CsPbBr 3 NCs within titania microspheres can convert CO 2 efficiently, with S-scheme charge transfer enhancing the separation of electron–hole pairs.…”